Hydraulic hammers are used on work sites to break up large hard objects before such objects can be moved away. Hydraulic hammers may be mounted to back hoes or excavators or other machines. Typically, the hammer assembly is powered by either a hydraulic or pneumatic pressure source or a combination of both. The hydraulic pressure, pneumatic pressure, or combination thereof is used to drive a movable piston downward within a housing. During the power stroke, the downward moving piston strikes a work tool, which, in turn, is driven in the downward direction. During its downward movement, the work tool strikes the object to be broken up. To assist in alignment between the moving piston and the work tool, hammer bushings are provided within the housing. During operation of the hydraulic hammer, the bushings can wear down causing increased clearance between the bushings and the work tool. The increased clearance can cause improper alignment and damage to the work tool and piston.
U.S. Pat. No. 7,152,692 to HURSKAINEN is directed to a hydraulic hammer having a sealing bushing. The sealing bushing includes a percussion piston that delivers strokes to a tool. A lower part of the percussion piston is sealed with respect to a frame by the sealing bushing. The sealing bushing includes one or more lower seals. The sealing bushing does not contribute to the bearing of the percussion piston and it is arranged in place through the lower end of the hydraulic hammer. However, no mechanism for adjusting clearance is provided.
The present disclosure is directed toward overcoming one or more of the problems discovered by the inventors or that is known in the art.